Data storage and retrieval today relies heavily on microfiche recording of the data. Microfiche drastically reduces required storage space for the data, makes the data easily accessible and is relatively inexpensive.
For satisfactory operation, microfilm requires great recording precision. Prior art recorders physically moved the film in the X-direction by moving it relative to the platen using roller drives. The platen paper and the film are removed in the Y-direction. This makes accurate positioning in the X-direction difficult. The film was supplied from a storage reel usually mounted at about the mid-point of one of the "X" or the "Y" direction movements to limit film distortion or twisting during recordation. Frequently, the exposed film is taken up in another cartridge. After a recording session is over, the exposed film is severed for developing. Each time this is done a substantial length of film is wasted.
The recordation takes place on film sections of a predetermined size and is carried out in rectilinear fashion. When a film section is filled with data, the film is advanced for data recordation on the next film section until the full length of film has been exposed. Thereafter, the film is developed and cut to size.
Prior art recorders have several shortcomings. A precise alignment of the tracks and the optics was frequently difficult to achieve and maintain. The required high accuracy in focusing microfiche images could thereby result in a compromised image quality. Film twisting during scanning could move the film section being exposed out of register resulting in inaccuracies in the data recordation and possible problems during data retrieval. Moreover, exposed film was frequently not available for appreciable periods of time until the full length of film stored on the storage reel has been exposed.